1. Field of the Invention
The present invention relates to a DRAM cylindrical capacitor and a method of fabricating the same. More particularly, the present invention relates to a DRAM cylindrical capacitor and a method of fabricating the same, reduction of yield caused by difficulty in growing a capacitor dielectric layer may be effectively reduced.
2. Description of Related Art
A semiconductor memory mainly comprises a transistor and a capacitor. In a high depth-to-width ratio semiconductor process, the size of the capacitor must be reduced so that it occupies comparatively smaller space in the device. As the memory space required for storage of software grows rapidly, the demand for corresponding increase in the number of capacitors also grows. Accordingly, it highly desired to develop the semiconductor process technology to meet this demand.
At present, larger capacitance may be achieved by increasing the surface area of the bottom electrode of the capacitor. For example, in a conventional cylindrical capacitor, the bottom electrode of the capacitor is made into a cylindrical form, and a Hemispherical Silicon Grain (HSG) structure is formed on the surface of the bottom electrode for increasing the area of the capacitor.
However, as the dimensions of the device proceeds towards further miniaturization, the bottom width of the cylindrical capacitor must be smaller. However, when a HSG structure is formed on the small width cylindrical capacitor, the bottom electrodes may be undesirably connected to each other, and thus the area of the capacitor is reduced.